Sunday, December 06, 2015

ViewSonic N3752w-1M how to enter to services mode – software update – dc dc power supply circuit

Contents of this article 

  • How to enter Service mode (factory mode )
  • How to update Firmware 
  • HDMI DDC key input
  • DC-DC power supply circuit 

VIEWSONIC N3752W-1

SERVICE MODE AND FIRMWARE UPDATE


Test Equipments 
PC signal generator: CHROMA 2525 CARD ,CHROMA 2327 or 2329,Pioneer
DV-S969AVi.
TV and Video signal generator.
Color analyzer: MINOLTA CA110.
Power meter: CP-310A or CP-320A.
AC power supply transformer: 110V/120V ±20% 60Hz ±5%.
Digital ammeter
Test Condition
Before function test and alignment, each LCD TV should be run-in and warmed up for a least 30 minutes with the following conditions:
(a) In room temperature,
(b) With full-white screen, and 16 grey scale,
(c) With cycled display modes.
Test Display Modes & Pattern
EEPROM INIT
A. Timing: 1360*768@60Hz
B. Pattern: 16*12 pane
C. ENTER FACTORY MODE.
How to enter to service mode (factory mode )
Press ’POWER’, ‘UP ARROW ’and ‘ENTER’ at the same time, then go into the FACTORY MODE.
D. Select EEPROM INITIAL and press ENTER. The act of EEPROM INITIAL is completed when EEPROM INIT disappeared.
COLOR TEMPERATURE ADJUSTING
PC MODE:
A. Timing: 1360*768@60Hz.
B. Pattern: 16 grey scale.
C. LCD TV should be run-in and warmed up for at least 30 minutes.
D. Make sure the distance between SENSOR of the CA110 and the LCD TV is about 20cm.
E. Color Temperature adjusting.
1. Under the picture 16 grey scale of VGA source, select WHITE BALANCE and press ENTER, The color warm will auto adjust. The act of EHITE BALANCEL is completed when the picture is steady.
2.After adjusting, switch to FULL WHITE and check the value of each color. 
Preset color for N3752W
x=0.283±0.015
y=0.297±0.015
3.Under the picture NTSC color bar of YPbPr source, select WHITE BALANCE and press ENTER, The color warm will auto adjust. The act of EHITE BALANCEL is completed when EHITE BALANCEL disappeared.
4.After adjusting, switch to FULL WHITE and check the value of each color. 
Preset color for N3752W
x=0.283±0.015
y=0.297±0.015
VGA DDC Key In Procedure
Note:
1. Every time after replacing the main board, you have to do the DDC key in.
2. If you find the DDC does not conform to the LCD TV, you have to do the DDC key in.
Equipment Needed
N3752W LCD TV
DDC Card
PC
RS-232 cable
Barcode Reader
VGA Cable
Setup Procedure
1.Connect VGA Card and DDC Card with RS-232 cable.
2. Barcode Reader connects with keyboard and PC keyboard port.
3. Connect DDC Card and N3752W LCD TV with VGA Cable. (when key in DVI DDC information, use VGA transform to DVI port )
4. Connect Power Cord to N3752W LCD TV.
DDC Key In Procedure
1. run DDC exe
2. Choose model number then
3. Press “ENTER” key.
4. Input bar code
5. Press “ENTER” key, then the successful picture is as follows. “DDC DOWNLOED OK.
6. Exit program.
HDMI DDC Key In Procedure
There are three EDID files for the different HDMI connectors. So you must be download the different EDID into each HDMI connector.
Equipment Needed
N3752W LCD TV
PC
RS-232 cable
Barcode Reader
HDMI Cable
Setup Procedure
1. Connect HDMI Card and DDC Card with RS-232 cable.
2. Barcode Reader connects with keyboard and PC keyboard port.
3. Connect DDC Card and N3752W LCD TV with HDMI Cable.
4. Connect Power Cord to N3752W LCD TV.
DDC Key In Procedure
1. Run DDC.exe
2. Choose model number then
3. Press “ENTER” key.
4, Input bar code
5. Press “ENTER” key, then the successful picture is as follows. “DDC DOWNLOED OK.
6. Exit program.
Firmware Upgrade Procedure
When you receive the returned LCD TV, please check whether the firmware version is the latest. If not, please do the following procedures to upgrade it to the latest version.
Equipment Needed
N3752W LCD TV
Fixture for Firmware Upgrade
VGA Cable
PC (Personal Computer)
Firmware Upgrade Program
One additional LCD TV for checking the program execution
Installing the USB device driver. The USB driver will be upgraded if necessary.
Insert the USB to RS232 Download Board to PC’s USB port. Then you can found the USB Device detected and follow Windows comments to finish the Driver install.
Execute the Mtktool to start download the file. The Mtktool program will be upgraded if necessary.
The Mtktool Operat
1. Select Platform : MT8105 , MT1389 ,MT8202 or MT8205.
2. Select COM port. Depends on the COM port assigned in System Device Manager.
3. Select Baud Rate. 115200x 8 (Suggestion)
4. Enable the USB Bridge.
5. Browsing the File to download.
6. Press Upgrade to download file.
Note :
1. The Baud Rate is auto setting if mismatch found between your platform and Mtktool.
2. You can slow down the baud rate if some Flash memory cannot works properly in high-speed download.
3. Please call the MediaTek contact window if any problem found like unsupported Flash Type or fail to download.
DC-DC POWER SUPPLY CIRCUIT 
CLICK ON THE IMAGE TO ZOOM IN